1. Technical Field
This invention relates to finishing machines used in finishing the inner trochoidal surface of a work piece, such as a rotary engine housing which requires uniform and precise finishing to achieve an effective seal between the trochoidal surface and the engine rotor which is well known and understood within the art.
2. Description of Prior Art
Prior Art devices of this type have used a variety of different designs to rotate either the housing about a fixed tool surface or guide the finishing tool around the trochoidal surface, see for example U.S. Pat. Nos. 3,812,574, 3,663,118, 3,693,297, 3,805,454, 3,921,339 and 3,982,356.
In U.S. Pat. No. 3,812,574 a finishing apparatus and process is disclosed that holds and rotates a work piece in a trochoidal path by securing the work piece to a holder having a cam surface that is driven by following drive wheel.
U.S. Pat. No. 3,663,188 is directed to a cam controlled grinding machine that has a driven cam engaged by rollers that are connected to a work piece support table. A fixed grinder tool engages the work piece as it and the table moves.
U.S. Pat. No. 3,693,297 discloses a fixed tool head and a cam driven work piece utilizing a pair of cams together to induce the required motion of the work piece in the trochoidal fashion.
In U.S. Pat. No. 3,805,454 a finishing machine is disclosed that moves a work piece in a trochoidal path by an offset gear drive shaft and a regulation assembly having a regulation shaft driven by the pinion offset gear.
U.S. Pat. No. 3,921,339 is directed to a trochoidal generating surface that uses a complex multi-shaft mechanism to impart trochoidal movement to a work piece mounting jig. The multiple shafts are engaged to one another by mesh gears and each is responsible for a particular point in the trochoidal path.
Finally in U.S. Pat. No. 3,982,356 a honing machine is disclosed that moves a tool in a trochoidal path to engage a fixed work piece.